Alpine Amplifier R Series 4-Ch Class D 100W Rms X 4 @ 4Ohm. 150W Rms X 4 @ 2 OhmThis new BBX amplifier gives you Alpine power performance at an amazing price. And theyre designed to fit easily in virtually any system. This amp delivers high output power and exceptional performance for their class. A great way to expand your sound system on a limited budget. High pass and low pass filters let you set the frequency points for the high, mid and bass ranges to match your speakers and ensure optimum efficiency. Performance With Bass